This invention relates to multi-purpose ammunition, and in particular to ammunition having a multiple range capability. Such type of ammunition is disclosed in U.S. Pat. No. 3,283,719 to Andrew J. Grandy. Such type of ammunition is also disclosed in our copending application Ser. No. 561,545, filed Dec. 14, 1983. In U.S. Pat. No. 3,283,719 there is disclosed a type of ammunition which can have multi-range capability which is at least partially independent from the requirement of increasing the gun barrel length. There are provided in the Grandy-type ammunition for this purpose at the rear end of the casing different types of propellant charges. These propellant charges are arranged parallel and adjacent to each other within a propellant chamber which has a wall that surrounds all of the propellant charges. These propellant charges are either singly or jointly ignitable by means fo separate primers.
The Grandy-type ammunition makes it possible to arrange the partial propellant charges eccentrically with respect to the ammunition axis as can be noted from FIGS. 6 and 7 of U.S. Pat. No. 3,283,719. This eccentric arrangement causes a streaming-out of the partial propellant charge gases eccentrically with respect to the ammunition axis. This constitutes an important inner ballistic drawback which may even damage the wing and/or fin-stabilization guiding means for the ammunition. This type of multi-purpose ammunition has therefore been found unsatisfactory.
Another drawback of the Grandy-type ammunition resides in that all of the propellant charges are fastened to the ammunition casing, so that when, utilizing only one propellant charge at least another propellant charge remains live and in a mechanically ignitable condition in the casing, whereby, for example, the personnel servicing the ammunition are exposed to seriour danger.
In view of the fact that each partial propellant charge must be separately ignited by individual separate firing pins via a corresponding igniting arrangement, the Grandy-type ammunition cannot be used in high cadence-firing machine cannons, because of the complex firing bolt construction and control. Consequently, due to the separate igniting of the corresponding partial propellant charge, an application of this type of ammunition in a machine cannon is furthermore not possible, because the propellant charge can generally only be ignited by means of one firing pin in a machine cannon.
A further drawback of this known type of ammunition resides in that the propellant charge casing for each propellant charge must be closed at its front end by a sealing disc so that, when one partial propellant charge is ignited, its gas production does not also ignite one of the other partial propellant charges. Such discs may remain in the ammunition casing while separating therefrom, or may remain in the gun barrel, so that under certain circumstances they can cause considerable disturbances in the firing cycle.